The capturing of an image, whether that image is being captured permanently on photographic film or as a digital still image, or whether the image is being captured as a moving image using a video camera or television camera or the like, nearly always first involves composing the image prior to capture. This is normally accomplished through a view finder or other similar arrangement associated with the camera apparatus. Successfully composing an image to produce a pleasing picture is a skill normally acquired over time and is a skill that inexperienced camera users often find difficult to acquire. Even experienced photographers or camera users can sometimes overlook some compositional aspects of an image due to a lack of concentration at the time of capture of the image, or due to capturing the image in a hurry.
A pleasingly composed image often follows one or more known composition rules. These rules include, for example, positioning elements of interest according to the “rule of thirds”, ensuring that elements of interest are not positioned too close to the edge of the image frame, framing the main area of interest by placing areas of very little interest at the edge of the image, for example placing relatively dark areas, or areas containing relatively little activity, at the edge of the image, and positioning strong diagonal lines to run towards the main subject of the image. The “rule of thirds” involves subdividing the image area using two equally spaced horizontal lines and two equally spaced vertical lines (in the manner of a “noughts and crosses” board) and positioning elements of interest on the intersections of the horizontal and vertical lines, or equally placing strong horizontal or vertical features on one of the horizontal and vertical lines.
Although these rules of composition are well known and can be studied, inexperienced photographers often find them difficult to apply. In particular, the lack of immediate feedback concerning the proposed composition of an image makes the learning process time consuming and difficult.
It has been proposed by the present applicant in the co-pending United Kingdom patent application number GB 0031423.7 to provide a method and system for automatically cropping an image after it has been captured to improve the composition of the image. The automatic cropping method disclosed in this co-pending application is based on automatic selection of one or more of the composition rules indicated above. While this post capture analysis and cropping is very useful, a disadvantage of this method is that by cropping an image after it has been captured the resulting cropped image is either smaller than the original image or is of a lower resolution than if the subject had been correctly framed in the first place. This is because inevitably by cropping the image its size is reduced and it is therefore necessary, in order to return the cropped image to the same size as the original image, to increase the size of each picture element that comprises the image. Also, cropping an image after it has been captured does not allow the full inclusion of any objects, or areas of interest, that were only partially included in the originally, poorly composed, image. Similarly, if there is inadequate border between the areas of interest and the edge of the original image, this cannot be corrected by subsequent post capture cropping.